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FXUS63 KILX 291131

National Weather Service Lincoln IL
531 AM CST SUN NOV 29 2015

.SHORT TERM...(Today)

08z/2am surface analysis shows a nearly stationary frontal boundary
draped from eastern Kentucky to Louisiana, while a 1031mb high
remains in place over western Wisconsin.  While the bulk of the
precipitation associated with the front has shifted well south and
east of Illinois, weak short-wave energy embedded within the
southwesterly flow pattern aloft has been triggering areas of very
light precipitation much further north into the cooler/drier
airmass.  Latest radar mosaic shows a few showers tracking across
northern Missouri/southern Iowa toward west-central Illinois.  Most
high-res models dissipate the showers as they cross the Mississippi
River and encounter a dry N/NE low-level flow around the Wisconsin
high: however, radar trends suggest otherwise.  Based on forward
progress of precip and surface obs showing precip reaching the
ground at a few sites in southeast Iowa, have decided to include a
slight chance PoP across the far W/NW KILX CWA for a few hours early
this morning.  With temperatures hovering near or slightly below
freezing in that area, have mentioned the potential for some very
light freezing rain across portions of Knox, Fulton, and Schuyler
counties through 7-8am.  Think precip will eventually dissipate as
it tracks further east toward the Illinois River, so will maintain a
dry forecast further east.  Aside from the early morning precip
potential across the west, much of the day will be dry.  Another
short-wave will begin to approach from the southwest late in the
day, with the Rapid Refresh consistently showing precip trying to
work back into west-central Illinois after 3pm.  Have therefore
included slight chance PoPs for rain showers along/west of a
Galesburg to Jacksonville line late in the day.  Due to overcast
conditions and a continued cool N/NE flow, have undercut MAV
guidance numbers by a few degrees...with afternoon highs only
reaching the lower to middle 40s.

.LONG TERM...(Tonight through Saturday)

00z Nov 29 models are in very good agreement concerning the break
down of the western CONUS Rex Block and the arrival of a storm
system late tonight into Monday.  As a closed upper low currently
over the Great Basin begins to pivot eastward, moisture poised just
upstream across the Southern Plains will begin to move back
northward into the area tonight.  This moisture will initially be
fighting a dry E/NE flow, so think much of the N/NE CWA will remain
dry through the entire night.  Have therefore introduced chance PoPs
for light rain southwest of the I-74 corridor, but have maintained a
dry forecast further northeast.  Best rain chances develop on
Monday, as profile saturates and stronger forcing associated with
approaching upper low arrives.  Will carry high chance to likely
PoPs across the board.  Surface low pressure will develop in advance
of the upper system across Kansas Monday morning, then will track
into western Wisconsin by Tuesday morning.  Once the low passes to
the north, a pronounced mid-level dry slot will work into the area
from the southwest late Monday night into Tuesday.  As a result,
precip chances will come to an end from southwest to northeast, with
dry conditions expected everywhere on Tuesday.  Will be a very
breezy day however, with southwesterly winds gusting to between 25
and 30mph.  The upper low will track across Wisconsin into the Great
Lakes Tuesday night into Wednesday morning, with wrap-around
moisture potentially affecting the northern CWA.  Models are in much
better agreement with their QPF, suggesting areas along/north of
I-74 may see a few snow-showers Tuesday night as the low skirts
by to the north.

Once the early week system exits the region, the remainder of the
extended will be quiet.  Models continue to show pronounced upper
ridging developing by the end of the week, so temperatures will
likely rise several degrees above normal.  Have therefore boosted
highs into the lower 50s on Friday, with lower to middle 50s by


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)

VFR conditions across central IL terminals this morning...and
should continue for much of the upcoming 24 hours. Low level
moisture ahead of an approaching storm system is expected to
begin returning to central IL in the early morning Monday...and
have brought MVFR ceilings back to KSPI by 09Z...but other sites
look like lower ceilings should hold off until around 12Z or
later. Winds expected to remain NE-E 6-10 kts through the period.


.ILX Watches/Warnings/Advisories...


LONG TERM...Barnes
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